EP0101862A2 - Druckkopf mit gesteuerter Tintentropfenerzeugung - Google Patents

Druckkopf mit gesteuerter Tintentropfenerzeugung Download PDF

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Publication number
EP0101862A2
EP0101862A2 EP83106870A EP83106870A EP0101862A2 EP 0101862 A2 EP0101862 A2 EP 0101862A2 EP 83106870 A EP83106870 A EP 83106870A EP 83106870 A EP83106870 A EP 83106870A EP 0101862 A2 EP0101862 A2 EP 0101862A2
Authority
EP
European Patent Office
Prior art keywords
drop
sections
transducer
produce
ink
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP83106870A
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English (en)
French (fr)
Other versions
EP0101862A3 (de
Inventor
Francis Chee-Shuen Lee
Ross Neal Mills
Grank Eberhard Talke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Business Machines Corp
Original Assignee
International Business Machines Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by International Business Machines Corp filed Critical International Business Machines Corp
Publication of EP0101862A2 publication Critical patent/EP0101862A2/de
Publication of EP0101862A3 publication Critical patent/EP0101862A3/de
Ceased legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01—Ink jet
    • B41J2/21—Ink jet for multi-colour printing
    • B41J2/2121—Ink jet for multi-colour printing characterised by dot size, e.g. combinations of printed dots of different diameter
    • B41J2/2128—Ink jet for multi-colour printing characterised by dot size, e.g. combinations of printed dots of different diameter by means of energy modulation

Definitions

  • This invention relates to ink jet printing apparatus and more particularly to ink jet printing apparatus in which ink drops are generated on demand in response to suitable electrical signals.
  • drop-on-demand ink jet printing apparatus which comprise a transducer and means for selectively energizing the transducer to eject a single drop of ink each time the transducer is energized.
  • the transducer comprises a plurality of separately actuable sections.
  • Print data is provided which defines a selected drop volume within the range of 1 to n drop volumes required for printing the print data.
  • Control means is provided which is operable in response to the print data to selectively actuate a particular combination of one or more of the separately actuable sections of the transducer to produce a drop of the volume specified by the print data.
  • the separately actuable sections of the transducer are of equal length so that a particular range of drop volumes can be produced with velocity within preselected limits. Should the drop velocity variation exceed the preselected limits, the drive signals to the selected transducer sections are varied in amplitude to achieve the required range of drop volumes. Should still further refinement in control be required to produce the selected number of drops of different volume within the preselected drop velocity limits, the pulse width of the drive signals is also varied.
  • the separately actuable sections of the transducer are of unequal length so that a greater range of drop volumes can be produced with velocity within preselected limits. Successively finer control can be achieved as in the first embodiment by a selective variation in the amplitude and pulse width of the drive signals to the separately actuable sections of the transducer.
  • the invention provides a drop-on-demand ink jet printing system comprising selectively energizable means to eject a single drop of ink each time the means is energized, characterised in that said ejection means comprise means capable of ejecting drops of selectively variable sizes so that said system is capable of grey scale printing, said means comprising a transducer having a plurality of separately actuable sections; and logic circuit control means to select a predetermined combination of sections for actuation to produce the selected drop size from among the available drop sizes.
  • the printer apparatus comprises a print head 10 to which is supplied liquid ink from ink supply means 12.
  • Control means 14 provides the voltage control pulses to selectively energize print head 10 to produce one ink drop 15 for each voltage signal supplied to print head 10.
  • Print head 10 comprises a transducer means 16 having an ink cavity 18 formed therein. Cavity 18 is maintained filled with ink through supply line 20 from ink supply means 12. Ink from supply means 12 is not pressurized so the ink in cavity 18 is maintained at or near atmospheric pressure under static conditions. An exit from cavity 18 is provided by nozzle portion 22 which is designed so that the ink does not flow out of or air does not flow into nozzle portion 22 under static conditions. In the embodiment shown in FIG.
  • transducer means 16 contracts and expands radially inward when energized with a suitable voltage pulse to thereby create a pressure wave in cavity 18 so that liquid ink is expelled out through nozzle portion 22 to form a single drop 15 of ink.
  • Control means 14 provides the voltage control pulses to selectively energize transducer means 16 to produce one ink drop for each voltage pulse applied to transducer means 16, and by a series of suitable voltage pulses a desired pattern can be produced on record member 24.
  • the transducer means 16 in the specific embodiment comprises a hollow cylindrical piezoelectric member 26 which forms ink cavity 18 in its enclosed interior.
  • Member 26 is divided into a plurality of separately actuable sections 28 by means of circumferential openings 30 in the outer conductive coating 32.
  • Each of the separately actuable sections is energized by a voltage pulse applied between that section's outer conductive coating 32 and inner conductive coating 34.
  • Inner conductive coating 34 is bridged across the end of piezoelectric member 26 away from nozzle plate 36 which closes one end of member 26 and includes nozzle portion 22.
  • An opening 30 is provided to separate a common terminal section 38 from the last separately actuable section 28.
  • Each of the sections 28 can be actuated-by a voltage pulse either alone or in combination with any other sections 28 to produce an ink drop having a volume proportional to the number of sections energized.
  • the velocity of the drops also changes depending upon the number of sections energized.
  • grey scale printing can be accomplished with this apparatus without undue distortion due to drop velocity variations particularly at lower drop rates.
  • One level of improvement can be achieved by selectively varying the amplitude of the drive signal. In this manner a closer match between the required drop volume and drop velocity can be achieved to improve print quality at higher drop rates.
  • a still further improvement can be achieved by controlling not only the amplitude of the drive signals but also the pulse width of the drive signals.
  • the print head comprises a transducer means 40 including a plurality of individually actuable sections 42, 42b, 42c, 42d, each of a different length.
  • n! drop volumes can be achieved by actuating different combinations of the individually actuable sections.
  • each of the individually actuable sections 42a-42d is substantially the same as that previously described for the print head shown in FIGS. 1 and 2.
  • the various options and combinations described there are equally applicable to this embodiment to produce grey scale printing having the required print quality and printing rate.
  • Control means 14 produces the drive voltage signals for each of the separate sections 28 or 42 to produce ink drops 15 of the volume required to print a chosen pattern on record member 24.
  • the chosen pattern is defined by PRINT DATA which is coupled to control means 14 in the form of a serial data stream.
  • a PRINT CLOCK signal also is coupled into control means 14 to synchronize movement and position of the print head 10 with the formation of the ink drop 15 so that the desired pattern is produced on record member 24.
  • control means 14 includes a stand alone microcomputer 41 of which a number of suitable models are now available as standard off-the-shelf items such as Zilog model Z-8, Intel models 8041, 8048 or 8051 and Motorola models 6801 and 6805. As the description proceeds, it will be obvious to those skilled in the art that equivalent hard-wired control circuits could as well be used, if desired.
  • Microcomputer 41 includes an ALU 43, a Random Access Storage (RAS) 45 for storing data, a Program Counter (P/C) 47 and a Read Only Store (ROS) 44 for storing the control program and control tables.
  • An interval Timer/Counter (T/C) 46 is provided to produce a timed output in response to clock pulses.
  • a series of output ports, PORT A, PORT B and PORT C provide latched output lines, and a serial PORT 48 receives the signals PRINT DATA and PRINT CLOCK which is used in conjunction with Interrupt Control (IC) 49.
  • the Machine Timing & Instruction Control (MT&IC) 51 produces control signals for the processor and multiplexed Address/Data Bus 53 connects the components of the microcomputer 41 to provide a path for transfer of data, control signals and addresses between components of the microcomputer 41.
  • the microcode control program is stored in ROS 44 at addresses 000 to 3FF (hexadecimal) (1K bytes), and the Drop Size ROS Look-Up Table is stored in ROS 44 at addresses 400 to 7FF (hexadecimal) (1K bytes).
  • the format of the Drop Size ROS Look-Up Table is shown in FIG. 5.
  • the serial data stream PRINT DATA is coupled into the Serial Port 48 of microcomputer 40 and this data includes one byte (8 bits) of data referred to as the Drop Size Code to define each drop size. Note that this format provides the capacity to define 256 different drop sizes.
  • FIG. 6 A graph showing the variation of drop volume with amplitude and pulse width at constant drop velocity for a specific design of print head is shown in FIG. 6. Should a sufficiently reliable model of the print head be available, the data for such a graph can be calculated. However, in some cases, the data must be generated empirically due to the large number of interrelated factor which affect the print head operation. Data similar to that shown in FIG. 6 is used to develop the data for the Drop Size ROS Look-Up Table.
  • the Drop Size Code 34 (hexadecimal) (53rd of the 256 combinations) is used to generate the ROS address which is given by 4X (Drop Size Code) +400 in the specific example of four segments 28 or 42.
  • the ROS address accesses the Data Segment Byte field, and this . field has one byte of data for each section 28 or 42 of the transducer (four in the specific embodiment).
  • the four bytes are stored in sequential locations.
  • the low order four bit field of each byte contains the information defining the drive voltage amplitude, and the high order four bit field of each byte contains information defining the drive pulse width or duration.
  • each four bit field has the capacity to define 16 different levels of either amplitude or pulse width. Note that, in the table for Drop Size Code 34, both amplitude and pulse width for segment numbers 2 and 4 are zero. This means that segments 2 and 4 are not energized for that particular drop size. However, for Drop Size Code E9 (234th of the 256 combinations), a non-zero value is stored for each segment, so in this case each of the four segments is driven.
  • the Data Segment Byte for segment 1 is accessed from ROS 44 and the low order 4-bit field is latched into the microcomputer output PORT A, and the high order 4-bit field is used to set up pulse duration timer 46 for segment 1 for output to one line in PORT C.
  • the second byte is accessed and the low order 4-bit field is latched into the remaining 4 lines of PORT A; and the high order 4-bit field is passed to the pulse duration timer setup routine to a second line in PORT C to control segment 2.
  • a similar procedure is followed for the last two data bytes to control segments 3 and 4 by latching the amplitude data is the 8 lines of PORT B and the pulse duration data into two additional lines of PORT C.
  • the data latched into PORT A and PORT B is coupled in four bit fields to a Digital to Analog Converter (DAC) 50 where the data is converted to analog form.
  • the output of the DAC 50 is coupled to Driver 52, one of which is provided for each of the segments 28 or 42.
  • DAC Digital to Analog Converter
  • All outputs of PORT C are turned ON to gate the appropriate Driver 52 to drive the corresponding segment 28 or 42 at the voltage amplitude of its respective DAC 50 according to the 4-bit codes in PORTS A & B.
  • Each transducer driver 52 is turned OFF individually by pulling the output lines of PORT C to the down level according to the pulse duration field for each transducer segment, which was used to initialize the timer routine.
  • the timer routine in a specific embodiment comprises a count down routine, but other routines may be used, if desired.
  • the control mode permits the pulse drive amplitude and pulse width to be easily controlled for each of the separate transducer sections.
  • the entry in the table would have the same amplitude field entry for each transducer section to be energized, and a zero entry for those transducer sections not to be energized.
  • the pulse width is controlled in the same manner.
  • the drop size code for no drop to be produced is all zeros for both the amplitude and pulse width fields. The largest drop volume is produced in response to drop size code number 255.

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  • Particle Formation And Scattering Control In Inkjet Printers (AREA)
EP83106870A 1982-08-30 1983-07-13 Druckkopf mit gesteuerter Tintentropfenerzeugung Ceased EP0101862A3 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US06/413,039 US4499479A (en) 1982-08-30 1982-08-30 Gray scale printing with ink jet drop-on demand printing head
US413039 1999-10-06

Publications (2)

Publication Number Publication Date
EP0101862A2 true EP0101862A2 (de) 1984-03-07
EP0101862A3 EP0101862A3 (de) 1985-12-27

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP83106870A Ceased EP0101862A3 (de) 1982-08-30 1983-07-13 Druckkopf mit gesteuerter Tintentropfenerzeugung

Country Status (3)

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US (1) US4499479A (de)
EP (1) EP0101862A3 (de)
JP (1) JPS5939556A (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0315206A2 (de) 1987-11-04 1989-05-10 Sharp Kabushiki Kaisha Punktdrucker
US5198833A (en) * 1987-11-04 1993-03-30 Sharp Kabushiki Kaisha Variable density ink-jet dot printer

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DE3317579A1 (de) * 1982-05-14 1983-11-17 Canon K.K., Tokyo Verfahren und einrichtung zur bilderzeugung
DE3326330C2 (de) * 1982-07-23 1994-06-09 Canon Kk Verfahren zur Erzeugung eines Graustufenbildes
JPS5941970A (ja) * 1982-09-01 1984-03-08 Canon Inc 画像形成方法及び装置
JPS5952658A (ja) * 1982-09-18 1984-03-27 Canon Inc 画像形成装置
GB2139450B (en) * 1983-03-08 1987-12-16 Canon Kk Color picture forming apparatus
US4635078A (en) * 1983-04-28 1987-01-06 Canon Kabushiki Kaisha Intermediate gradient image producing method
JPS60152172A (ja) * 1984-01-19 1985-08-10 Canon Inc カラ−画像形成装置
JPS6125365A (ja) * 1984-07-13 1986-02-04 Canon Inc 中間調画像形成方法
US4562445A (en) * 1984-07-26 1985-12-31 Metromedia, Inc. Apparatus and method for driving ink jet printer
US4599626A (en) * 1984-08-02 1986-07-08 Metromedia, Inc. Ink drop ejecting head
EP0203534A1 (de) * 1985-05-29 1986-12-03 Siemens Aktiengesellschaft Tintenschreibeinrichtung zur Erzeugung von Tintentröpfchen unterschiedlicher Grösse
US4746935A (en) * 1985-11-22 1988-05-24 Hewlett-Packard Company Multitone ink jet printer and method of operation
JPS62140851A (ja) * 1985-12-17 1987-06-24 Canon Inc インクジエツト記録ヘツド
US5172141A (en) * 1985-12-17 1992-12-15 Canon Kabushiki Kaisha Ink jet recording head using a piezoelectric element having an asymmetrical electric field applied thereto
JPS63166545A (ja) * 1986-12-19 1988-07-09 ゼロックス　コーポレーション スポットサイズ可変の音響プリンタ
US5617123A (en) * 1987-05-20 1997-04-01 Canon Kabushiki Kaisha Image processing method utilizing multiple binarizing and recording agent depositing steps
SE8702613L (sv) * 1987-06-24 1988-12-25 Kaileg Ab Transportanordning
JP2793593B2 (ja) * 1988-03-16 1998-09-03 株式会社リコー 液体噴射記録ヘッド
US4982199A (en) * 1988-12-16 1991-01-01 Hewlett-Packard Company Method and apparatus for gray scale printing with a thermal ink jet pen
US5070410A (en) * 1989-03-21 1991-12-03 Hewlett-Packard Company Apparatus and method using a combined read/write head for processing and storing read signals and for providing firing signals to thermally actuated ink ejection elements
US5107276A (en) * 1989-07-03 1992-04-21 Xerox Corporation Thermal ink jet printhead with constant operating temperature
US5146236A (en) * 1989-12-14 1992-09-08 Ricoh Company, Ltd. Ink jet record apparatus
DE69016396T2 (de) * 1990-01-08 1995-05-18 Tektronix Inc Verfahren und Gerät zum Drucken mit in der Grösse veränderbaren Tintentropfen unter Verwendung eines auf Anforderung reagierenden Tintenstrahl-Druckkopfes.
US5270484A (en) * 1990-09-14 1993-12-14 Canon Kabushiki Kaisha Powder conveying device
DE4318978C2 (de) * 1993-06-08 1996-09-05 Heidelberger Druckmasch Ag Piezoelektrischer Aktuator
US5625397A (en) * 1994-11-23 1997-04-29 Iris Graphics, Inc. Dot on dot ink jet printing using inks of differing densities
CN1331672C (zh) 1994-12-29 2007-08-15 佳能株式会社 采用喷墨头的喷墨设备及预喷射方法
US6142599A (en) * 1995-06-29 2000-11-07 Canon Kabushiki Kaisha Method for ink-jet recording and an ink-jet recording apparatus
US5901425A (en) 1996-08-27 1999-05-11 Topaz Technologies Inc. Inkjet print head apparatus
JP3289624B2 (ja) * 1996-11-25 2002-06-10 ミノルタ株式会社 インクジェットヘッドの駆動装置
US6020905A (en) * 1997-01-24 2000-02-01 Lexmark International, Inc. Ink jet printhead for drop size modulation
US6070973A (en) * 1997-05-15 2000-06-06 Massachusetts Institute Of Technology Non-resonant and decoupled droplet generator
US6042211A (en) * 1997-11-25 2000-03-28 Hewlett-Packard Company Ink drop volume variance compensation for inkjet printing
US6305773B1 (en) 1998-07-29 2001-10-23 Xerox Corporation Apparatus and method for drop size modulated ink jet printing
US6471337B1 (en) * 1998-10-27 2002-10-29 Canon Kabushiki Kaisha Ink-jet printing apparatus, ejection recovery method for ink-jet printing apparatus, and fabrication method of ink-jet printing head
US6296811B1 (en) * 1998-12-10 2001-10-02 Aurora Biosciences Corporation Fluid dispenser and dispensing methods
US6629739B2 (en) 1999-12-17 2003-10-07 Xerox Corporation Apparatus and method for drop size switching in ink jet printing
US6601948B1 (en) * 2002-01-18 2003-08-05 Illinois Tool Works, Inc. Fluid ejecting device with drop volume modulation capabilities
US7077334B2 (en) * 2003-04-10 2006-07-18 Massachusetts Institute Of Technology Positive pressure drop-on-demand printing
ITTO20030467A1 (it) * 2003-06-20 2004-12-21 Fiat Ricerche Procedimento e dispositivo per l'eiezione di micro-gocce
CN102131646B (zh) * 2008-06-30 2014-05-21 富士胶卷迪马蒂克斯股份有限公司 喷墨

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US3683212A (en) * 1970-09-09 1972-08-08 Clevite Corp Pulsed droplet ejecting system
US3787884A (en) * 1973-01-08 1974-01-22 Ibm Ink jet printer
US4251824A (en) * 1978-11-14 1981-02-17 Canon Kabushiki Kaisha Liquid jet recording method with variable thermal viscosity modulation
US4222060A (en) * 1978-11-20 1980-09-09 Ricoh Company, Ltd. Ink jet printing apparatus
GB2084083A (en) * 1980-09-11 1982-04-07 Exxon Research Engineering Co Method and apparatus for tuning ink jets

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0315206A2 (de) 1987-11-04 1989-05-10 Sharp Kabushiki Kaisha Punktdrucker
EP0315206A3 (en) * 1987-11-04 1989-09-27 Sharp Kabushiki Kaisha Dot printer
US5198833A (en) * 1987-11-04 1993-03-30 Sharp Kabushiki Kaisha Variable density ink-jet dot printer

Also Published As

Publication number Publication date
US4499479A (en) 1985-02-12
EP0101862A3 (de) 1985-12-27
JPS5939556A (ja) 1984-03-03

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